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A089809
Complement of
A078588
.
4
0, 1, 0, 1, 1, 0, 1, 0, 0, 1, 0, 1, 1, 0, 1, 0, 0, 1, 0, 1, 0, 0, 1, 0, 1, 1, 0, 1, 0, 0, 1, 0, 1, 1, 0, 1, 0, 1, 1, 0, 1, 0, 0, 1, 0, 1, 1, 0, 1, 0, 0, 1, 0, 1, 0, 0, 1, 0, 1, 1
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OFFSET
1,1
COMMENTS
a(n) = 1 if (fractional part of n*r) < 1/2, else a(n) = 0, where r = golden ratio = (1 + sqrt(5))/2. -
Clark Kimberling
, Dec 27 2016
LINKS
Clark Kimberling,
Table of n, a(n) for n = 1..10000
FORMULA
a(n) = 1 if
A078588
= 0; otherwise, not.
a(n) = 1 iff
A024569
is not 1.
a(n) = 1 iff
A089808
is 1.
a(n) = 1 if (fractional part of n*r) < 1/2, else a(n) = 0. -
Clark Kimberling
, Dec 27 2016
EXAMPLE
1. a(7) = 1 since
A078588
(7) = 0
2. a(7) = 1 since
A024569
is not 1 (
A024569
(7) = 3).
3. a(7) = 1 since
A089808
(7) = 1.
MATHEMATICA
r = GoldenRatio; z = 500;
Table[If[FractionalPart[n r] < 1/2, 1, 0 ], {n, 1, z}] (*
A089809
*)
Table[If[FractionalPart[n r] > 1/2, 1, 0 ], {n, 1, z}] (*
A078588
*)
1 - % (*
A089809
,
Clark Kimberling
, Dec 27 2016 *)
PROG
(Python)
from math import isqrt
def
A089809
(n): return ((n+isqrt(5*n**2))&1)^1 #
Chai Wah Wu
, Aug 17 2022
CROSSREFS
Cf.
A078588
,
A024569
,
A089808
.
Sequence in context:
A368909
A285249
A269027
*
A165211
A341389
A188027
Adjacent sequences:
A089806
A089807
A089808
*
A089810
A089811
A089812
KEYWORD
nonn
AUTHOR
Gary W. Adamson
, Nov 11 2003
STATUS
approved